Buggy code:
public class StringUtilsTest extends TestCase { static final String WHITESPACE ; static final String NON_WHITESPACE ; static final String TRIMMABLE ; static final String NON_TRIMMABLE ; private static final String [ ] ARRAY_LIST = new String [ ] { "foo" , "bar" , "baz" } ; private static final String [ ] EMPTY_ARRAY_LIST = new String [ ] { } ; private static final String [ ] NULL_ARRAY_LIST = new String [ ] { null } ; private static final String [ ] MIXED_ARRAY_LIST = new String [ ] { null , "" , "foo" } ; private static final Object [ ] MIXED_TYPE_LIST = new Object [ ] { new String ( "foo" ) , new Long ( 2 ) } ; private static final String SEPARATOR = "," ; private static final char SEPARATOR_CHAR = ';' ; private static final String TEXT_LIST = "foo,bar,baz" ; private static final String TEXT_LIST_CHAR = "foo;bar;baz" ; private static final String TEXT_LIST_NOSEP = "foobarbaz" ; private static final String FOO_UNCAP = "foo" ; private static final String FOO_CAP = "Foo" ; private static final String SENTENCE_UNCAP = "foo<seq2seq4repair_space>bar<seq2seq4repair_space>baz" ; private static final String SENTENCE_CAP = "Foo<seq2seq4repair_space>Bar<seq2seq4repair_space>Baz" ; public StringUtilsTest ( String name ) { } public void testConstructor ( ) { } public void testCaseFunctions ( ) { } public void testSwapCase_String ( ) { } public void testJoin_Objectarray ( ) { } public void testJoin_ArrayChar ( ) { } public void testJoin_ArrayString ( ) { } public void testJoin_IteratorChar ( ) { } public void testJoin_IteratorString ( ) { } public void testJoin_IterableChar ( ) { } public void testJoin_IterableString ( ) { } public void testSplit_String ( ) { } public void testSplit_StringChar ( ) { } public void testSplit_StringString_StringStringInt ( ) { } private void innerTestSplit ( char separator , String sepStr , char noMatch ) { } public void testSplitByWholeString_StringStringBoolean ( ) { } public void testSplitByWholeString_StringStringBooleanInt ( ) { } public void testSplitByWholeSeparatorPreserveAllTokens_StringStringInt ( ) { } public void testSplitPreserveAllTokens_String ( ) { } public void testSplitPreserveAllTokens_StringChar ( ) { } public void testSplitPreserveAllTokens_StringString_StringStringInt ( ) { } private void innerTestSplitPreserveAllTokens ( char separator , String sepStr , char noMatch ) { } public void testSplitByCharacterType ( ) { } public void testSplitByCharacterTypeCamelCase ( ) { } public void testDeleteWhitespace_String ( ) { } public void testReplace_StringStringString ( ) { } public void testReplace_StringStringStringInt ( ) { } public void testReplaceOnce_StringStringString ( ) { } public void testReplace_StringStringArrayStringArray ( ) { } public void testReplace_StringStringArrayStringArrayBoolean ( ) { } public void testReplaceChars_StringCharChar ( ) { } public void testReplaceChars_StringStringString ( ) { } public void testOverlay_StringStringIntInt ( ) { } public void testRepeat_StringInt ( ) { } public void testRepeat_StringStringInt ( ) { } public void testChop ( ) { } public void testChomp ( ) { } public void testRightPad_StringInt ( ) { } public void testRightPad_StringIntChar ( ) { } public void testRightPad_StringIntString ( ) { } public void testLeftPad_StringInt ( ) { } public void testLeftPad_StringIntChar ( ) { } public void testLeftPad_StringIntString ( ) { } public void testLength ( ) { } public void testCenter_StringInt ( ) { } public void testCenter_StringIntChar ( ) { } public void testCenter_StringIntString ( ) { } public void testReverse_String ( ) { } public void testReverseDelimited_StringChar ( ) { } public void testDefault_String ( ) { } public void testDefault_StringString ( ) { } public void testDefaultIfEmpty_StringString ( ) { } public void testAbbreviate_StringInt ( ) { } public void testAbbreviate_StringIntInt ( ) { } private void assertAbbreviateWithOffset ( String expected , int offset , int maxWidth ) { } public void testDifference_StringString ( ) { } public void testDifferenceAt_StringString ( ) { } public void testGetLevenshteinDistance_StringString ( ) { } public void testEMPTY ( ) { } public void testIsAllLowerCase ( ) { } public void testIsAllUpperCase ( ) { } public void testRemoveStart ( ) { } public void testRemoveStartIgnoreCase ( ) { } public void testRemoveEnd ( ) { } public void testRemoveEndIgnoreCase ( ) { assertNull ( "removeEndIgnoreCase(null,<seq2seq4repair_space>null)" , StringUtils . removeEndIgnoreCase ( null , null ) ) ; assertNull ( "removeEndIgnoreCase(null,<seq2seq4repair_space>\"\")" , StringUtils . removeEndIgnoreCase ( null , "" ) ) ; assertNull ( "removeEndIgnoreCase(null,<seq2seq4repair_space>\"a\")" , StringUtils . removeEndIgnoreCase ( null , "a" ) ) ; assertEquals ( "removeEndIgnoreCase(\"\",<seq2seq4repair_space>null)" , StringUtils . removeEndIgnoreCase ( "" , null ) , "" ) ; assertEquals ( "removeEndIgnoreCase(\"\",<seq2seq4repair_space>\"\")" , StringUtils . removeEndIgnoreCase ( "" , "" ) , "" ) ; assertEquals ( "removeEndIgnoreCase(\"\",<seq2seq4repair_space>\"a\")" , StringUtils . removeEndIgnoreCase ( "" , "a" ) , "" ) ; assertEquals ( "removeEndIgnoreCase(\"www.domain.com.\",<seq2seq4repair_space>\".com\")" , StringUtils . removeEndIgnoreCase ( "www.domain.com." , ".com" ) , "www.domain.com." ) ; assertEquals ( "removeEndIgnoreCase(\"www.domain.com\",<seq2seq4repair_space>\".com\")" , StringUtils . removeEndIgnoreCase ( "www.domain.com" , ".com" ) , "www.domain" ) ; assertEquals ( "removeEndIgnoreCase(\"www.domain\",<seq2seq4repair_space>\".com\")" , StringUtils . removeEndIgnoreCase ( "www.domain" , ".com" ) , "www.domain" ) ; assertEquals ( "removeEndIgnoreCase(\"domain.com\",<seq2seq4repair_space>\"\")" , StringUtils . removeEndIgnoreCase ( "domain.com" , "" ) , "domain.com" ) ; assertEquals ( "removeEndIgnoreCase(\"domain.com\",<seq2seq4repair_space>null)" , StringUtils . removeEndIgnoreCase ( "domain.com" , null ) , "domain.com" ) ; <START_BUG> assertEquals ( "removeEndIgnoreCase(\"www.domain.com\",<seq2seq4repair_space>\".com\")" , StringUtils . removeEndIgnoreCase ( "www.domain.com" , ".COM" ) , "www.domain" ) ; <END_BUG> } public void testRemove_String ( ) { } public void testRemove_char ( ) { } public void testDifferenceAt_StringArray ( ) { } public void testGetCommonPrefix_StringArray ( ) { } public void testStartsWithAny ( ) { } }

Fix:
assertEquals ( "removeEndIgnoreCase(\"www.domain.com\",<seq2seq4repair_space>\".COM\")" , StringUtils . removeEndIgnoreCase ( "www.domain.com" , ".COM" ) , "www.domain" ) ;